Backlight unit and display device having backlight unit

ABSTRACT

A backlight unit is discussed, which includes a frame including a bottom and a sidewall extending from the bottom; at least one substrate located on the frame, and a plurality of light sources mounted on the at least one substrate; and a reflecting sheet located on the at least one substrate, wherein the reflecting sheet includes: a first sheet part located on the bottom, the first sheet part including a plurality of holes corresponding to the plurality of the light sources; a second sheet part extended from the first sheet part, the second sheet part including first areas and second areas; and a third sheet part extended from the second sheet part and located on the sidewall.

This application claims the benefit of U.S. Provisional Application No.62/073,509 filed on Oct. 31, 2014, and the priority benefit of KoreanPatent Application No. 10-2015-0109158 filed in the Korean IntellectualProperty Office on Jul. 31, 2015, the entire contents of which areincorporated herein by reference for all purposes as if fully set forthherein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a backlight unit and a display devicecomprising it.

2. Discussion of the Related Art

With the development of the information society, various demands fordisplay devices have been increasing. Various display devices, such asliquid crystal displays (LCDs), plasma display panels (PDPs),electroluminescent displays (ELDs), and vacuum fluorescent displays(VFDs), have been recently studied and used to meet various demands forthe display devices.

Among the display devices, a liquid crystal display panel of the liquidcrystal display includes a liquid crystal layer, and a thin filmtransistor (TFT) substrate and a color filter substrate which arepositioned opposite each other with the liquid crystal layer interposedtherebetween. The liquid crystal display panel displays an image usinglight provided by a backlight unit of the liquid crystal display.

SUMMARY OF THE INVENTION

The present disclosure provides a backlight unit including a reflectingsheet having a dot area.

In one aspect, there is a backlight unit including a frame including abottom and a sidewall extending from the bottom; at least one substratelocated on the frame, and a plurality of light sources mounted on the atleast one substrate; and a reflecting sheet located on the at least onesubstrate, wherein the reflecting sheet includes: a first sheet partlocated on the bottom, the first sheet part including a plurality ofholes corresponding to the plurality of the light sources; a secondsheet part extended from the first sheet part, the second sheet partincluding first areas and second areas; and a third sheet part extendedfrom the second sheet part and located on the sidewall, wherein thefirst areas correspond to outermost holes among the plurality of holes,and the second areas are located between the first areas,

wherein a dot pattern in the first areas is different from a dot patternin the second areas, wherein the dot pattern in at least one of thefirst areas and the second areas includes a plurality of dot areaspositioned sequentially in a direction from the first sheet part to thethird sheet part, the plurality of dot areas including first dot areasand second dot areas, the first dot areas including a plurality of dotshaving the same size and the second dot areas including a plurality ofdots having the same size, and wherein a size of the plurality of dotsin the first dot areas is different from a size of the plurality of dotsin the second dot areas.

At least one of the first dot areas and the second dot areas protrudestoward the first sheet part.

The first dot areas protrudes toward the first sheet part.

The first dot areas protrudes toward the first sheet part excluding onefirst dot area adjacent to a corner of the reflecting sheet.

The first dot areas have the same first dot pattern, and the second dotareas have the same second dot pattern different from the first dotpattern.

The pluralities of dots of the first dot areas and the second dot areasare positioned on a horizontal dot area formed along a first side of thereflecting sheet and a vertical dot area formed along a second side ofthe reflecting sheet, and a first distance between a point nearest tothe third sheet part in the horizontal dot area and a hole nearest tothe horizontal dot area among the plurality of holes is different from asecond distance between a point nearest to the third sheet part in thevertical dot area and a hole nearest to the vertical dot area.

The pluralities of dots of the first dot areas and the second dot areasare positioned on a horizontal dot area formed along a first side of thereflecting sheet and a vertical dot area formed along a second side ofthe reflecting sheet, and a third distance between a point nearest tothe first sheet part in the horizontal dot area and a hole nearest tothe horizontal dot area among the plurality of holes is different from afourth distance between a point nearest to the first sheet part in thevertical dot area and a hole nearest to the vertical dot area.

The pluralities of dots of the first dot areas and the second dot areasare positioned on a horizontal dot area formed along a first side of thereflecting sheet and a vertical dot area formed along a second side ofthe reflecting sheet, and a fifth distance between a point nearest tothe first sheet part and a point nearest to the third sheet part in thehorizontal dot area is different from a sixth distance between a pointnearest to the first sheet part and a point nearest to the third sheetpart in the vertical dot area.

A size of a dot of the first dot areas nearest to the first sheet partis different from a size of a dot of the second dot areas nearest to thefirst sheet part.

In the second sheet part, at least one of a size and a density of thepluralities of dots of the first dot areas and the second dot areasincreases as the pluralities of dots approach the third sheet part.

In the second sheet part, at least one of a size and a density of thepluralities of dots of the first dot areas and the second dot areasincreases as the pluralities dots approach the third sheet part along animaginary line connecting a first point of a corner area of thereflecting sheet and a second point closest to the third sheet part inthe middle of the second sheet part.

In the second sheet part, at least one of a size and a density of dotsof a first area adjacent to the third sheet part is different from atleast one of a size and a density of dots of a second area except thefirst area.

The first area is one of the first dot areas, and at least one of a sizeand a density of at least one dot of the first area is smaller than atleast one of a size and a density of at least one dot of the second dotareas.

The pluralities of dots of the first dot areas and the second dot areasare positioned on a horizontal dot area formed along a first side of thereflecting sheet and a vertical dot area formed along a second side ofthe reflecting sheet, and at least one of the horizontal and verticaldot areas has different widths, the widths being in a direction from thefirst sheet part to the third sheet part.

At least one of the horizontal and vertical dot areas includes a centerarea and side areas positioned on the sides of the center area, and awidth of the center area is smaller than widths of the side areas.

A dot pattern of the center area is different from a dot pattern of theside areas.

At least one protrusion area protruding from the side areas to the firstsheet part.

At least one of a size and a density of at least one dot of the at leastone protrusion area is different from at least one of a size and adensity of at least one dot adjacent to the at least one protrusionarea.

A width of at least a portion of the at least one horizontal dot area isdifferent from a width of at least another portion of the at least onehorizontal dot area.

Each of the first areas corresponds to each of the outermost holes amongthe plurality of holes.

In another aspect, there is a backlight unit including: a frameincluding a bottom and a sidewall extending from the bottom; at leastone substrate located on the frame, and a plurality of light sourcesmounted on the at least one substrate; and a reflecting sheet located onthe at least one substrate, wherein the reflecting sheet includes: afirst sheet part located on the bottom, the first sheet part including aplurality of holes corresponding to the plurality of the light sources;a second sheet part extended from the first sheet, the second sheet partincluding first areas and second areas; and a third sheet part extendedfrom the second sheet and located on the sidewall, wherein the firstareas correspond to outermost holes among the plurality of holes, andthe second areas are located between the first areas, wherein a dotpattern in the first areas is different from a dot pattern in the secondareas, wherein the dot pattern in at least one of the first areas andthe second areas includes a plurality of dot areas positionedsequentially in a direction from the first sheet part to the third sheetpart, the plurality of dot areas including first dot areas and seconddot areas, the first dot areas including a plurality of dots having thesame size and the second dot areas including a plurality of dots havingthe same size, and wherein a distance of adjacent dots in the first dotareas is different from a distance of adjacent dots in the second dotareas.

In another aspect, there is a display device including: a frameincluding a bottom and a sidewall extending from the bottom; at leastone substrate located on the frame, and a plurality of light sourcesmounted on the at least one substrate; a reflecting sheet located on theat least one substrate, an optical sheet located on the reflectingsheet; and a display panel located on the optical sheet, wherein thereflecting sheet includes: a first sheet part located on the bottom, thefirst sheet part including a plurality of holes corresponding to theplurality of the light sources; a second sheet part extended from thefirst sheet, the second sheet part including first areas and secondareas; and a third sheet part extended from the second sheet and locatedon the sidewall, wherein the first areas correspond to outermost holesamong the plurality of holes, and the second areas are located betweenthe first areas, wherein a dot pattern in the first areas is differentfrom a dot pattern in the second areas, wherein the dot pattern in atleast one of the first areas and the second areas includes a pluralityof dot areas positioned sequentially in a direction from the first sheetpart to the third sheet part, the plurality of dot areas including firstdot areas and second dot areas, the first dot areas including aplurality of dots having the same size and the second dot areasincluding a plurality of dots having the same size, and wherein a sizeof the plurality of dots in the first dot areas is different from a sizeof the plurality of dots in the second dot areas.

Each of the first areas may be corresponding to each of outermost holesamong the plurality of holes.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention. In the drawings:

FIGS. 1 and 2 illustrate a display device according to an exampleembodiment of the invention;

FIGS. 3 to 7 illustrate configuration of a display device related to anexample embodiment of the invention;

FIGS. 8 and 9 illustrate a light source according to an exampleembodiment of the invention;

FIG. 10 illustrates a connection relationship between a reflecting sheetand components around the reflecting sheet according to an exampleembodiment of the invention;

FIGS. 11 to 13 illustrate configuration of a reflecting sheet accordingto an example embodiment of the invention;

FIGS. 14 to 17 illustrate a dot distribution of a reflecting sheetaccording to an example embodiment of the invention;

FIGS. 18 and 19 illustrate a reflecting sheet according to an exampleembodiment of the invention;

FIG. 20 illustrates a dot distribution of a reflecting sheet accordingto an example embodiment of the invention; and

FIGS. 21 and 27 illustrate a dot distribution of a reflecting sheetaccording to an example embodiment of the invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to embodiments of the invention,examples of which are illustrated in the accompanying drawings. Whereverpossible, the same reference numbers will be used throughout thedrawings to refer to the same or like parts. A suffix such as “module”and “unit” may be assigned or used interchangeably to refer to elementsor components. Use of such a suffix herein is merely intended tofacilitate the description of the embodiments of the invention, and thesuffix itself is not intended to give any special meaning or function.It will be paid attention that detailed description of known arts willbe omitted if it is determined that the description of the known artscan obscure the embodiments of the invention. The accompanying drawingsare merely intended to easily describe the embodiments of the invention,and the spirit and technical scope of the present invention is notlimited by the accompanying drawings. It should be understood that thepresent invention is not limited to specific disclosed embodiments, butincludes all modifications, equivalents and substitutes included withinthe spirit and technical scope of the present invention.

Hereinafter, the embodiments of the invention are described using aliquid crystal display panel as an example of a display panel. Otherdisplay panels may be used. For example, a plasma display panel (PDP), afield emission display (FED) panel, and an organic light emitting diode(OLED) display panel may be used.

In what follows, a display panel may include a first long side LS1, asecond long side LS2 opposite the first long side LS1, a first shortside SS1 adjacent to the first long side LS1 and the second long sideLS2, and a second short side SS2 opposite the first short side SS1.

In the embodiment disclosed herein, the first short side SS1 may bereferred to as a first side area; the second short side SS2 may bereferred to as a second side area opposite the first side area; thefirst long side LS1 may be referred to as a third side area which isadjacent to the first side area and the second side area and ispositioned between the first side area and the second side area; and thesecond long side LS2 may be referred to as a fourth side area which isadjacent to the first side area and the second side area, is positionedbetween the first side area and the second side area, and is opposite tothe third side area.

The embodiment of the invention describes that lengths of the first andsecond long sides LS1 and LS2 are longer than lengths of the first andsecond short sides SS1 and SS2 for the sake of brevity and ease ofreading. However, the lengths of the first and second long sides LS1 andLS2 may be almost equal to the lengths of the first and second shortsides SS1 and SS2.

In the following description, a first direction DR1 may be a directionparallel to the long sides LS1 and LS2 of the display panel, and asecond direction DR2 may be a direction parallel to the short sides SS1and SS2 of the display panel.

Further, a third direction DR3 may be a direction vertical to the firstdirection DR1 and/or the second direction DR2.

In the embodiment disclosed herein, the first direction DR1 and thesecond direction DR2 may be commonly referred to as a horizontaldirection.

Further, the third direction DR3 may be referred to as a verticaldirection.

FIGS. 1 and 2 illustrate a display device according to an exampleembodiment of the invention.

As shown in FIGS. 1 and 2, a display device 100 according to theembodiment of the invention may include a display panel 110 and a backcover 150 positioned in the rear of the display panel 110.

The back cover 150 may be connected to the display panel 110 in asliding manner in a direction (i.e., the second direction DR2) from thefirst long side LS1 to the second long side LS2. In other words, theback cover 150 may be inserted into the first short side SS1, the secondshort side SS2 opposite the first short side SS1, and the first longside LS1 which is adjacent to the first and second short sides SS1 andSS2 and is positioned between the first short side SS1 and the secondshort side SS2, of the display panel 110 in the sliding manner.

The back cover 150 and/or other components adjacent to the back cover150 may include a protrusion, a sliding unit, a connection unit, etc.,so that the back cover 150 is connected to the display panel 110 in thesliding manner.

FIGS. 3 to 7 illustrate configuration of a display device related to theembodiment of the invention.

As shown in FIG. 3, the display device 100 according to the embodimentof the invention may include a front cover 105, the display panel 110, abacklight unit 120, a frame 130, and the back cover 150.

The front cover 105 may cover at least a portion of a front surface anda side surface of the display panel 110. The front cover 105 may have arectangular fame shape, in which a center portion is empty. Because thecenter portion of the front cover 105 is empty, an image displayed onthe display panel 110 may be seen to the outside.

The front cover 105 may include a front cover and a side cover. Namely,the front cover 105 may include the front cover positioned at the frontsurface of the display panel 110 and the side cover at the side surfaceof the display panel 110. The front cover and the side cover may beseparately configured. One of the front cover and the side cover may beomitted. For example, the front cover may be omitted, and only the sidecover may be absent in terms of a beautiful appearance of the displaydevice 100.

The display panel 110 may be positioned in front of the display device100 and may display an image. The display panel 110 may divide the imageinto a plurality of pixels and may output the image while controllingcolor, brightness, and chroma of each pixel. The display panel 110 mayinclude an active area, on which the image is displayed, and an inactivearea, on which the image is not displayed. The display panel 110 mayinclude a front substrate and a back substrate which are positionedopposite each other with a liquid crystal layer interposed therebetween.

The front substrate may include a plurality of pixels each includingred, green, and blue subpixels. The front substrate may generate animage corresponding to the red, green, or blue color in response to acontrol signal.

The back substrate may include switching elements. The back substratemay turn on pixel electrodes. For example, the pixel electrode maychange a molecule arrangement of the liquid crystal layer in response toa control signal received from the outside. The liquid crystal layer mayinclude a plurality of liquid crystal molecules. The arrangement of theliquid crystal molecules may change depending on a voltage differencebetween the pixel electrode and a common electrode. The liquid crystallayer may transmit light provided by the backlight unit 120 to the frontsubstrate.

The backlight unit 120 may be positioned at a back surface of thedisplay panel 110. The backlight unit 120 may include a plurality oflight sources. The light sources of the backlight unit 120 may bearranged in an edge type or a direct type. In an instance of the edgetype backlight unit 120, a light guide plate may be added.

The backlight unit 120 may be coupled to a front surface of the frame130. For example, the plurality of light sources may be disposed at thefront surface of the frame 130. In this instance, the backlight unit 120may be commonly called the direct type backlight unit 120.

The backlight unit 120 may be driven in an entire driving method or apartial driving method such as a local dimming method and an impulsivedriving method. The backlight unit 120 may include an optical sheet 125and an optical layer 123.

The optical sheet 125 can cause light of the light sources to beuniformly transferred to the display panel 110. The optical sheet 125may include a plurality of layers. For example, the optical sheet 125may include at least one prism sheet and/or at least one diffusionsheet.

The optical sheet 125 may further include at least one coupling unit 125d. The coupling unit 125 d may be coupled to the front cover 105 and/orthe beck cover 150. Namely, the coupling unit 125 d may be directlycoupled to the front cover 105 and/or the back cover 150. Alternatively,the coupling unit 125 d may be coupled to a structure formed on thefront cover 105 and/or the back cover 150. Namely, the coupling unit 125d may be indirectly coupled to the front cover 105 and/or the back cover150.

The optical layer 123 may include the light source, etc. The detailedconfiguration of the optical layer 123 will be described in thecorresponding paragraphs.

The frame 130 may support components constituting the display device100. For example, the frame 130 may be coupled to the backlight unit120. The frame 130 may be formed of a metal material, for example, analuminum alloy.

The back cover 150 may be positioned at a back surface of the displaydevice 100. The back cover 150 may protect inner configuration of thedisplay device 100 from the outside. At least a portion of the backcover 150 may be coupled to the frame 130 and/or the front cover 105.The back cover 150 may be an injection production (or injection molded)formed of a resin material.

FIG. 4 shows the configuration of the optical sheet 125.

As shown in (a) of FIG. 4, the optical sheet 125 and/or a diffusionplate 129 may be positioned on the frame 130. The optical sheet 125and/or the diffusion plate 129 may be coupled to the frame 130 at anedge of the frame 130. The optical sheet 125 and/or the diffusion plate129 may be directly placed at the edge of the frame 130. Namely, anouter perimeter of the optical sheet 125 and/or the diffusion plate 129may be supported by the frame 130. An upper surface of an edge of theoptical sheet 125 and/or the diffusion plate 129 may be surrounded by afirst guide panel 117. For example, the optical sheet 125 and/or thediffusion plate 129 may be positioned between the edge of the frame 130and a flange 117 a of the first guide panel 117.

The display panel 110 may be positioned at a front surface of theoptical sheet 125. An edge of the display panel 110 may be coupled tothe first guide panel 117. Namely, the display panel 110 may besupported by the first guide panel 117.

An edge area of the front surface of the display panel 110 may besurrounded by the front cover 105. For example, the display panel 110may be positioned between the first guide panel 117 and the front cover105.

As shown in (b) of FIG. 4, the display device 100 according to theembodiment of the invention may further include a second guide panel113. The optical sheet 125 and/or the diffusion plate 129 may be coupledto the second guide panel 113. Namely, the second guide panel 113 mayhave a shape, in which the second guide panel 113 is coupled to theframe 130 and the optical sheet 125 and/or the diffusion plate 129are/is coupled to the second guide panel 113. The second guide panel 113may be formed of a material different from the frame 130. The frame 130may have a shape surrounding the first and second guide panels 117 and113.

As shown in (c) of FIG. 4, in the display device 100 according to theembodiment of the invention, the front cover 105 may not cover the frontsurface of the display panel 110. Namely, one end of the front cover 105may be positioned on the side of the display panel 110.

Referring to FIGS. 5 and 6, the backlight unit 120 may include theoptical layer 123 including substrates 122, at least one light assembly124, a reflecting sheet 126 and the diffusion plate 129, and the opticalsheet 125 positioned on a front surface of the optical layer 123.

The substrates 122 may include a plurality of straps, which extend in afirst direction and are separated from one another by a predetermineddistance in a second direction perpendicular to the first direction.

At least one light assembly 124 may be mounted on the substrate 122. Thesubstrate 122 may have an electrode pattern for connecting an adaptor tothe light assembly 124. For example, a carbon nanotube electrode patternfor connecting the adaptor to the light assembly 124 may be formed onthe substrate 122.

The substrate 122 may be formed of at least one of polyethyleneterephthalate (PET), glass, polycarbonate (PC), and silicon. Thesubstrate 122 may be a printed circuit board (PCB), on which at leastone light assembly 124 is mounted.

The light assemblies 124 may be disposed on the substrate 122 atpredetermined intervals in the first direction. A diameter of the lightassembly 124 may be greater than a width of the substrate 122. Namely,the diameter of the light assembly 124 may be greater than a length ofthe substrate 122 in the second direction.

The light assembly 124 may be one of a light emitting diode (LED) chipand a LED package having at least one LED chip.

The light assembly 124 may be configured as a colored LED emitting atleast one of red, green, and blue light or a white LED. The colored LEDmay include at least one of a red LED, a green LED, and a blue LED.

The light source included in the light assembly 124 may be a COB(Chip-On-Board) type. The COB light source may have a configuration, inwhich the LED chip as the light source is directly coupled to thesubstrate 122. Thus, the process may be simplified. Further, aresistance may be reduced, and a loss of energy resulting from heat maybe reduced. Namely, power efficiency of the light assembly 124 mayincrease. The COB light source can provide the brighter lighting and maybe implemented to be thinner and lighter than a related art.

The reflecting sheet 126 may be positioned at the front surface of thesubstrate 122. The reflecting sheet 126 may be positioned in an areaexcluding a formation area of the light assemblies 124 of the substrates122. Namely, the reflecting sheet 126 may have a plurality of holes 235.

The reflecting sheet 126 may reflect light emitted from the lightassembly 124 to a front surface of the reflecting sheet 126. Further,the reflecting sheet 126 may again reflect light reflected from thediffusion plate 129.

The reflecting sheet 126 may include at least one of metal and metaloxide which are a reflection material. The reflecting sheet 126 mayinclude metal and/or metal oxide having a high reflectance, for example,aluminum (Al), silver (Ag), gold (Au), and titanium dioxide (TiO₂).

The reflecting sheet 126 may be formed by depositing and/or coating themetal or the metal oxide on the substrate 122. An ink including themetal material may be printed on the reflecting sheet 126. On thereflecting sheet 126, a deposition layer may be formed using a heatdeposition method, an evaporation method, or a vacuum deposition methodsuch as a sputtering method. On the reflecting sheet 126, a coatinglayer and/or a printing layer may be formed using a printing method, agravure coating method or a silk screen method.

An air gap may be positioned between the reflecting sheet 126 and thediffusion plate 129. The air gap may serve as a buffer capable of widelyspreading light emitted from the light assembly 124. A supporter 200 maybe positioned between the reflecting sheet 126 and the diffusion plate129, so as to maintain the air gap.

A resin may be deposited on the light assembly 124 and/or the reflectingsheet 126. The resin may function to diffuse light emitted from thelight assembly 124.

The diffusion plate 129 may upwardly diffuse light emitted from thelight assembly 124.

The optical sheet 125 may be positioned at a front surface of thediffusion plate 129. A back surface of the optical sheet 125 may beadhered to the diffusion plate 129, and a front surface of the opticalsheet 125 may be adhered to the back surface of the display panel 110.

The optical sheet 125 may include at least one sheet. More specifically,the optical sheet 125 may include one or more prism sheets and/or one ormore diffusion sheets. The plurality of sheets included in the opticalsheet 125 may be attached and/or adhered to one another.

In other words, the optical sheet 125 may include a plurality of sheetshaving different functions. For example, the optical sheet 125 mayinclude first to third optical sheets 125 a to 125 c. The first opticalsheets 125 a may function as a diffusion sheet, and the second and thirdoptical sheets 125 b and 125 c may function as a prism sheet. A numberand/or a position of the diffusion sheets and the prism sheets may bechanged. For example, the optical sheet 125 may include the firstoptical sheets 125 a as the diffusion sheet and the second optical sheet125 b as the prism sheet.

The diffusion sheet may prevent light coming from the diffusion platefrom being partially concentrated and may homogenize a luminance of thelight. The prism sheet may concentrate light coming from the diffusionsheet and may make the concentrated light be vertically incident on thedisplay panel 110.

The coupling unit 125 d may be formed on at least one of corners of theoptical sheet 125. The coupling unit 125 d may be formed in at least oneof the first to third optical sheets 125 a to 125 c.

The coupling unit 125 d may be formed at the corner on the long side ofthe optical sheet 125. The coupling unit 125 d formed on the first longside and the coupling unit 125 d formed on the second long side may beasymmetric. For example, a number and/or a position of the couplingunits 125 d formed on the first long side may be different from a numberand/or a position of the coupling units 125 d formed on the second longside.

Referring to FIG. 7, the substrates 122 including the plurality ofstraps, which extend in the first direction and are separated from oneanother by a predetermined distance in the second directionperpendicular to the first direction, may be provided on the frame 130.One end of each of the plurality of substrates 122 may be connected to aline electrode 232.

The line electrode 232 may extend in the second direction. The lineelectrode 232 may be connected to the ends of the substrates 122 atpredetermined intervals in the second direction. The substrates 122 maybe electrically connected to the adaptor through the line electrode 232.

The light assemblies 124 may be mounted on the substrate 122 atpredetermined intervals in the first direction. A diameter of the lightassembly 124 may be greater than a width of the substrate 122 in thesecond direction. Hence, an outer area of the light assembly 124 may bepositioned beyond a formation area of the substrate 122.

FIGS. 8 and 9 show a light source according to the embodiment of theinvention.

As shown in FIG. 8, a light source 203 may be a COB light source. TheCOB light source 203 may include at least one of an emission layer 135,first and second electrodes 147 and 149, and a fluorescent layer 137.

The emission layer 135 may be positioned on the substrate 122. Theemission layer 135 may emit one of red, green, and blue light. Theemission layer 135 may include one of Firpic, (CF3ppy)2Ir(pic),9,10-di(2-naphthyl)anthracene(AND), perylene, distyrybiphenyl, PVK,OXD-7, UGH-3(Blue), and a combination thereof.

The first and second electrodes 147 and 149 may be positioned on bothsides of a lower surface of the emission layer 135. The first and secondelectrodes 147 and 149 may transmit an external driving signal to theemission layer 135.

The fluorescent layer 137 may cover the emission layer 135 and the firstand second electrodes 147 and 149. The fluorescent layer 137 may includea fluorescent material converting light of a spectrum generated from theemission layer 135 into white light. A thickness of the emission layer135 on the fluorescent layer 137 may be uniform. The fluorescent layer137 may have a refractive index of 1.4 to 2.0.

The COB light source 203 according to the embodiment of the inventionmay be directly mounted on the substrate 122. Thus, the size of thelight assembly 124 may decrease.

Because heat dissipation of the light sources 203 is excellent byforming the light sources 203 on the substrate 122, the light sources203 may be driven at a high current. Hence, a number of light sources203 required to secure the same light quantity may decrease.

Further, because the light sources 203 are mounted on the substrate 122,a wire bonding process may not be necessary. Hence, the manufacturingcost may be reduced due to the simplification of the manufacturingprocess.

As shown in FIG. 9, the light source 203 according to the embodiment ofthe invention may emit light in a first emission range EA1. Namely, thelight source 203 may emit light in the first emission range EA1including a second emission range EA2 of the front side and third andfourth emission ranges EA3 and EA4 of both sides. Thus, the light source203 according to the embodiment of the invention is different from arelated art POB light source emitting light in the second emission rangeEA2. In other words, the light source 203 according to the embodiment ofthe invention may be the COB light source, and the COB light source 203may emit light in a wide emission range including the side.

Because the COB light source 203 emits light even in a directioncorresponding to the third and fourth emission ranges EA3 and EA4 of theside, the embodiment of the invention needs to efficiently control lightof the side direction. The reflecting sheet according to the embodimentof the invention may control a reflectance of light emitted from thelight source 203 in the side direction. Thus, the embodiment of theinvention may reduce the non-uniformity of brightness resulting fromlight of the side direction.

FIG. 10 illustrates a connection relationship between the reflectingsheet and components around the reflecting sheet according to theembodiment of the invention.

As shown in FIG. 10, the reflecting sheet 126 according to theembodiment of the invention may be placed on the frame 130. For example,the reflecting sheet 126 may be coupled to a receiving unit 132 formedinside the frame 130.

The reflecting sheet 126 may include a horizontal coupling unit HH and avertical coupling unit VH. For example, coupling holes may be formedalong a long side and/or a short side of the reflecting sheet 126.

The horizontal coupling unit HH and the vertical coupling unit VH may beinserted into a horizontal protrusion 130H and/or a vertical protrusion130V formed on the frame 130. A guide panel GP may be formed on thereflecting sheet 126.

The guide panel GP may be formed of plastic material of injectionmolding or press processed metal material. The guide panel GP may becoupled to the horizontal protrusion 130H and/or the vertical protrusion130V. When the guide panel GP is coupled to the reflecting sheet 126,the reflecting sheet 126 may be fixed between the frame 30 and the guidepanel GP. FIG. 10 shows that the long sides and the short sides of theguide panel GP are separated from one another, as an example. The guidepanel GP, which the long sides and the short sides are connected to oneanother, may be used.

The reflecting sheet 126 placed on the frame 130 may be configured as athree-dimensional shape corresponding to a shape of the receiving unit132. Even when the reflecting sheet 126 according to the embodiment ofthe invention has the three-dimensional shape, the reflecting sheet 126can provide an optimum reflection effect. For example, the reflectingsheet 126 can uniformly reflect light throughout its entire area.

The reflecting sheet 126 may constitute a portion of the backlight unit120 (refer to FIG. 5). The substrate 122, on which the light sources 203are mounted, may be positioned between the reflecting sheet 126 and theframe 130.

The plurality of substrates 122 may be arranged in the horizontaldirection and/or the vertical direction. The substrates 122 may beconnected to signal lines 121 connected to a controller, etc., of thedisplay device 100. The signal lines 121 may be connected to thesubstrates 122 through holes formed in the frame 130.

The reflecting sheet 126 may include a plurality of lens holes 235. Theplurality of lens holes 235 may correspond to the light sources 203 onthe substrate 122. For example, the plurality of lens holes 235 may bearranged in the horizontal direction and/or the vertical directioncorrespondingly to the light sources 203. A lens 124 b may be insertedinto the lens hole 235. For example, the lens 124 b may be coupled tothe light source 203 through the lens hole 235.

The reflecting sheet 126 may include a plurality of support holes 205. Asupporter 200 may be coupled to the support hole 205. The supporter 200may support the optical sheet 125 and/or the diffusion plate 129positioned in front of the reflecting sheet 126. Namely, the reflectingsheet 126 may be separated from the optical sheet 125 and/or thediffusion plate 129 at a predetermined distance.

The reflecting sheet 126 may include a plurality of fixing pin holes206. A fixing pin 202 may be coupled to the fixing pin hole 206. Also,the fixing pin 202 may be coupled to a frame hole 204 formed in theframe 130. Thus, the fixing pin 202 may fix the reflecting sheet 126 tothe frame 130.

FIGS. 11 to 13 illustrate configuration of the reflecting sheetaccording to the embodiment of the invention.

As shown in FIGS. 11 to 13, the reflecting sheet 126 according to theembodiment of the invention may be placed in an inner area of the frame130. The reflecting sheet 126 placed on the frame 130 may have thethree-dimensional shape corresponding to a shape of the frame 130.

As shown in FIG. 11, the frame 130 may include first to third frameareas 130 a to 130 c.

The first frame area 130 a may be a bottom surface of the frame 130. Thesecond frame area 130 b may be substantially flat. Namely, the secondframe area 130 b may be a surface positioned on an X-Y plane of thedisplay device 100.

The second frame area 130 b may be a sidewall surface extended upwardlyfrom the first frame area 130 a. The second frame area 130 b may extendin a direction parallel to a Z-axis direction or a direction inclined tothe Z-axis direction. The receiving unit 132 (refer to FIG. 10) may beformed inside the frame 130 by the second frame area 130 b serving as asidewall of the frame 130.

The third frame area 130 c may be a surface extended from the secondframe area 130 b in an X-axis direction. The third frame area 130 c maybe substantially parallel to the first frame area 130 a. Namely, thethird frame area 130 c may be a flat surface in the same manner as thefirst frame area 130 a at a height level different from the first framearea 130 a by the second frame area 130 b.

The third frame area 130 c may include a protruding area. The thirdframe area 130 c may be coupled to a protrusion formed through aseparate process. The protruding area and/or the protrusion of the thirdframe area 130 c may be coupled to the reflecting sheet 126. Forexample, the protruding area and/or the protrusion of the third framearea 130 c may be coupled to a third sheet area 126 c of the reflectingsheet 126. The protruding area and/or the protrusion of the third framearea 130 c may be coupled to the optical sheet 125 (refer to FIG. 5).

The reflecting sheet 126 may be coupled to an area formed by the firstto third frame areas 130 a to 130 c of the frame 130. For example, thereflecting sheet 126 may be coupled to the first frame area 130 athrough the fixing pin 202. When a portion of the reflecting sheet 126is coupled to the first frame area 130 a through the fixing pin 202, theportion of the reflecting sheet 126 may naturally contact the frame 130.

When the reflecting sheet 126 is coupled to the frame 130 through thefixing pin 202, the shape of the reflecting sheet 126 may be naturallychanged depending on the shape of the frame 130. Namely, a naturallyrounded second sheet area 126 b of the reflecting sheet 126 may beformed. Thus, a separate process for forming a chamfer of the reflectingsheet 126 may not be necessary, and workability may be improved.

The reflecting sheet 126 may include first to third sheet areas 126 a to126 c. Namely, an area of the reflecting sheet 126 may be divideddepending on whether or not the reflecting sheet 126 and the frame 130contact each other. For example, the area of the reflecting sheet 126may be divided into a contact area contacting the frame 130 and anon-contact area not contacting the frame 130.

The area of the reflecting sheet 126 may be divided into the first sheetarea 126 a and the second sheet area 126 b by the fixing pin 202. Inother words, the second sheet area 126 b may be an area between thefixing pin 202 and a portion contacting the third frame area 130 c,Namely, the first sheet area 126 a and the second sheet area 126 b maybe determined depending on whether or not the reflecting sheet 126contacts the first frame area 130 a of the frame 130. The second sheetarea 126 b may be naturally separated from the frame 130 by propertiesand elasticity of the reflecting sheet 126. For example, when the firstsheet area 126 a is coupled to the frame 130 by the fixing pin 202, thesecond sheet area 126 b may naturally form a curved surface by its ownweight and may be separated from the frame 130. A separation space 130 dmay be formed between the second sheet area 126 b and the frame 130. Anangle formed by the second sheet area 126 b of the reflecting sheet 126and the bottom surface of the frame 130 may gradually increase. Namely,in the non-contact area of the reflecting sheet 126, the reflectingsheet 126 may have a two-dimensional curve shape. Thus, the second sheetarea 126 b may be separated from the frame 130 at a predetermined angle.

The third sheet area 126 c may be placed in the third frame area 130 c.The third sheet area 126 c may be coupled to the third frame area 130 c.Alternatively, the third sheet area 126 c may be naturally positioned onthe third frame area 130 c. Namely, the third sheet area 126 c maycontact the third frame area 130 c by elastic force of the Z-axisdirection resulting from the rounded second sheet area 126 b.

Light L may be emitted through the lens 124 b. Namely, light generatedin the light source 203 may be emitted to the outside through the lens124 b. The light L emitted through the lens 124 b may travel throughvarious paths. For example, a portion of the light L may travel througha path of the side direction of the lens 124 b.

The portion of the light L in the path of the side direction may traveltoward the second sheet area 126 b. At least a portion of lightgenerated in the light source 203 may be totally reflected inside thelens 124 b and may travel toward the second sheet area 126 b. In thisinstance, an amount of light L upwardly travelling in the second sheetarea 126 b may be more than an amount of light L downwardly travellingin the second sheet area 126 b. In other words, an amount and/or adensity of light L transferred to the reflecting sheet 126 may benon-uniform. When the amount and/or the density of the light L is notuniform, a viewer watching the display device 100 may perceivenon-uniformity of the amount and/or the density of the light L. Forexample, when an amount of light L incident on an upper portion of thesecond sheet area 126 b is more than an amount of light L incident on alower portion of the second sheet area 126 b, a corresponding area maybe recognized as being brighter than other areas because of the light Lreflected from the upper portion of the second sheet area 126 b.

As shown in FIG. 12, an angle formed by an extension line from aboundary between the first sheet area 126 a and the second sheet area126 b to a boundary between the second sheet area 126 b and the thirdsheet area 126 c and two straight lines parallel to the X-axis directionmay be called “A”. An inclined angle of the second sheet area 126 busing an intersection point P between the second sheet area 126 b and astraight line of the angle A as a starting point may increase. Namely,an angle of the second sheet area 126 b passing the intersection point Pin the X-axis direction may sharply increase.

Because the angle of the second sheet area 126 b passing theintersection point P increases, a density of the light L emitted fromthe lens 124 b (refer to FIG. 11) per unit area may further increase.Thus, a corresponding portion may be seen as being brighter than otherportions. As a result, the viewer may feel that the light is notuniform. The display device 100 according to the embodiment of theinvention can make light be uniformly reflected from the reflectingsheet 126. Hence, the viewer cannot feel or can feel less thenon-uniformity of the light.

As shown in FIG. 13, in the display device 100 according to theembodiment of the invention, dots DT may be formed in at least a portionof the reflecting sheet 126.

The dot DT may be an area having a pattern different from other areas.The dot DT may be an area of uneven portions (or concave-convexportions) formed on the reflecting sheet 126. The dot DT may be an area,in which at least a portion of the reflecting sheet 126 is colored. Forexample, the dot DT may be an area of a relatively dark color. Forexample, the dot DT may be a black or gray area. The dot DT may be anarea, in which the uneven portion and the colored portion are mixed witheach other. The dot DT may have a geometric shape, in which there is adifference in at least one of a shape, a size, a location, and a color.For example, the dot DT may be one of various shapes including a circle,an oval, a rectangle, a rod, a triangle, etc., formed on the reflectingsheet 126 and/or a combination of the various shapes.

The dots DT may affect a reflectance of a corresponding area. Namely,the dots DT may change a reflectance of light. For example, thereflectance of light may be reduced depending on at least one of ashape, a size, a location, and a color of the dot DT. The plurality ofdots DT may gather (or arranged) and form a dot area DA.

The dot area DA may be a gathering (or arranging) of the dots DT.Namely, the dot area DA may be a formation area of the plurality of dotsDT, which are the same as or different from one another in at least oneof a shape, a size, a location, and a color. For example, the dot areaDA may be formed in at least a portion of the second sheet area 126 b.As described above, a density of light per unit area in the second sheetarea 126 b may be high because of the inclined shape of the second sheetarea 126 b. The dot area DA may change a reflectance of light incidenton the second sheet area 126 b. In other words, a density of incidentlight per unit area is high, but a density of reflected light per unitarea may decrease. Thus, a phenomenon, in which a contrast of a portioncorresponding to the second sheet area 126 b is different from acontrast of other portions, may be prevented. Namely, light can beuniformly reflected from the entire reflecting sheet 126 because of thedot area DA. The dots DT constituting the dot area DA may be dividedinto a plurality of groups having different attributes. For example, aformation area of dots having a first attribute may be called a firstarea, and a formation area of dots having a second attribute may becalled a second area. Hereinafter, the dot area DA may be displayed bychanging the color, the density, etc., of the reflecting sheet 126, andareas having the different colors, densities, etc., may be formationareas of dots having different attributes even if a separate explanationis not given. For example, dots having different attributes may bedisposed in an area with a first color and an area with a second color.Namely, dots, which are different from one another in at least one ofthe size, the density, the color, and the interval, may be disposed indifferent areas.

The reflecting sheet 126 may further include a non-dot area NDA. Thenon-dot area NDA may be an area, in which there is no dot DT. Thenon-dot area NDA may be positioned in various areas of the reflectingsheet 126. For example, the non-dot area NDA may include first andsecond non-dot areas NDA1 and NDA2.

A width of the non-dot area NDA may be greater than a distance betweenadjacent dots. Namely, the width of the non-dot area NDA in a directionfrom the first sheet area 126 a to the third sheet area 126 c may begreater than a distance between two dots adjacent to the non-dot areaNDA. The width of the non-dot area NDA may be equal to or greater than 2mm.

The second non-dot area NDA2 may be positioned at a boundary between thesecond sheet area 126 b and the third sheet area 126 c. The secondnon-dot area NDA2 may be positioned in the second sheet area 126 b atthe boundary between the second sheet area 126 b and the third sheetarea 126 c.

The second non-dot area NDA2 may be an uppermost area of the secondsheet area 126 b and thus may be close to the optical sheet 125 and/orthe diffusion plate 129 positioned in front of the reflecting sheet 126.Hence, if the dot DT exists in the second non-dot area NDA2, the user ofthe display device 100 may observe the dot DT. Thus, the dot DT may notexist in the second non-dot area NDA2.

FIGS. 14 to 23 illustrate a dot distribution of the reflecting sheetaccording to the embodiment of the invention.

As shown in FIGS. 14 to 23, the dots DT of the reflecting sheet 126according to the embodiment of the invention may be disposed in variousshapes.

As shown in (a) of FIG. 14, the dots DT may be disposed in the dot areaDA. The adjacent dots DT may be separated from each other by a firstdistance O1. Namely, the dots DT may be disposed at regular intervals ofthe first distance O1.

The distance between the dots DT may affect the reflectance of thereflecting sheet 126. For example, when the distance between the dots DTdecreases, the reflectance may decrease.

As shown in (b) of FIG. 14, the adjacent dots DT may be separated fromeach other by the first distance O1, and the adjacent dots DT may beseparated from each other by a second distance O2. Namely, a distancebetween the dots DT may not be uniform

As shown in (a) of FIG. 15, the dot area DA may be divided into aplurality of areas. For example, the dot area DA may be divided into afirst area P1 and a second area P2. An attribute of dots DT included inthe first area P1 may be different from an attribute of dots DT includedin the second area P2. For example, at least one of a size, a density,and a color of a first dot DT1 in the first area P1 may be differentfrom at least one of a size, a density, and a color of a second dot DT2in the second area P2.

The second area P2 may be positioned further outside than the first areaP1. Namely, the second area P2 may be an area close to the third sheetarea 126 c. The second dot DT2 of the second area P2 may be larger thanthe first dot DT1 of the first area P1. Thus, a reflectance of thesecond area P2 may be less than a reflectance of the first area P1.

As shown in (b) of FIG. 15, the dot area DA may be divided into aplurality of areas. For example, the dot area DA may be divided intofirst to third areas P1 to P3. First to third dots DPI to DP3 of thefirst to third areas P1 to P3 may have different attributes. Forexample, the second dot DT2 may be larger than the first dot DT1, andthe third dot DT3 may be larger than the second dot DT2. Alternatively,the first to third dots DPI to DP3 have the same size, but a density ofthe first area P1 may be different from a density of the second area P2,and a density of the second area P2 may be different from a density ofthe third area P3. For example, the density of the first area P1 may beless than the density of the second area P2, and the density of thesecond area P2 may be less than the density of the third area P3.

As shown in FIG. 16, the dot area DA may not be divided into a pluralityof areas. However, dots DT included in the dot area DA may be differentfrom each other in at least one of a size, a density, and a color. Forexample, as the dot DT goes along the X-axis direction, the size of thedot DT may gradually increase. Namely, an attribute of the dot DTincluding at least one of the size, the density, and the color maygradually change.

As shown in (a) of FIG. 17, a size of the dot DT may gradually changedepending on a location.

As shown in (b) of FIG. 17, a size of the dot DT may sharply changedepending on a location. For example, the size of the dot DT may bechanged in a curve shape of a quadratic function.

FIGS. 18 and 19 illustrate a reflecting sheet according to an exampleembodiment of the invention.

As shown in FIGS. 18 and 19, the reflecting sheet 126 according to theembodiment of the invention may include the dot area DA.

The dot area DA may be formed along the long side and/or the short sideof the reflecting sheet 126. Namely, the dot area DA may be formed inthe corner area of the reflecting sheet 126. In other words, the dotarea DA may be formed in the second sheet area 126 b (refer to FIG. 11)of the reflecting sheet 126 placed in the receiving unit 132 (refer toFIG. 10) of the frame 130 (refer to FIG. 10).

The dot area DA may include first and second horizontal dot areas HDA1and HDA2 and first and second vertical dot areas VDA1 and VDA2. Thefirst and second horizontal dot areas HDA1 and HDA2 are represented asthe horizontal dot area HDA, and the first and second vertical dot areasVDA1 and VDA2 are represented as the vertical dot area VDA, except inthe instance where they need to be distinguished from each other.

A shape of the horizontal dot area HDA may be different from a shape ofthe vertical dot area VDA. For example, the shape of the horizontal dotarea HDA may not be symmetric to the shape of the vertical dot area VDAbased on a cutting portion S1 positioned at the corner of the reflectingsheet 126.

The reflecting sheet 126 may include lens holes 235 for coupling thelenses 124 b (refer to FIG. 11), fixing pin holes 206, supporter holes205, a horizontal coupling unit HH, and a vertical coupling unit VH.

The lens holes 235 may be disposed in parallel with one another alongthe horizontal and vertical directions based on the size of the displaydevice 100.

The fixing pin hole 206 may be coupled to the fixing pin 202 (refer toFIG. 10) for fixing the reflecting sheet 126 to the frame 130 (refer toFIG. 10). The fixing pin hole 206 may be positioned adjacent to theoutermost lens hole 235. For example, the fixing pin hole 206 may bepositioned between the adjacent lens holes 235 or between the lens hole235 and the dot area DA.

The fixing pin hole 206 may be positioned adjacent to the lens hole 235disposed on the outermost side. For example, the fixing pin hole 206 maybe positioned closer to the outermost side than the outermost lens hole235. For example, the fixing pin hole 206 may be positioned at alocation overlapping the outermost lens hole 235.

When the fixing pin 202 (refer to FIG. 10) is coupled to the frame 130(refer to FIG. 10) through the fixing pin hole 206, the second sheetarea 126 b may be naturally formed. Namely, when the fixing pin 202(refer to FIG. 10) is coupled to the frame 130 (refer to FIG. 10)through the fixing pin hole 206 formed in the horizontal and verticaldirections, a round chamfer may be formed in the outer area of thereflecting sheet 126.

A distance between the fixing pin holes 206 may be differently set. Forexample, a number of fixing pin holes 206 positioned in a horizontalcenter area HCA may be more than a number of fixing pin holes 206positioned in other areas based on the horizontal direction of thereflecting sheet 126.

A distance between the fixing pin holes 206 positioned in the horizontalcenter area HCA may be called a first horizontal distance HD1, and adistance between the fixing pin holes 206 positioned in areas other thanthe horizontal center area HCA may be called a second horizontaldistance HD2. The first horizontal distance HD1 may be less than thesecond horizontal distance HD2. Namely, the fixing pin holes 206 in thehorizontal center area HCA may be more densely disposed. Thus, a roundchamfer may be naturally formed at the four upper, lower, left, andright corners of the reflecting sheet 126 while the reflecting sheet 126is efficiently fixed.

The fixing pin holes 206 disposed in the vertical direction may exist.For example, the fixing pin holes 206 may be disposed along the left andright short sides of the reflecting sheet 126.

The fixing pin holes 206 on the first short side SS1 may be disposed atpredetermined intervals of a first vertical distance VD1. The fixing pinholes 206 on the second short side SS2 may be disposed at predeterminedintervals of a second vertical distance VD2. The first vertical distanceVD1 and the second vertical distance VD2 may be different from eachother. The second vertical distance VD2 may be greater than the firstvertical distance VD1.

A difference between the first vertical distance VD1 and the secondvertical distance VD2 may be generated by a shape of the frame 130coupled to the reflecting sheet 126. For example, the difference betweenthe first vertical distance VD1 and the second vertical distance VD2 maybe generated by a coupling space of a rib for assisting rigidity of theframe 130 and/or various electronic parts coupled to the frame 130. Thesupporter holes 205 may be coupled to the supporters 200. The supporterholes 205 may support the diffusion plate 129 (refer to FIG. 5) and/orthe optical sheet 125 (refer to FIG. 5) on the reflecting sheet 126. Thesupporter holes 205 may be positioned in the middle of the reflectingsheet 126 for the efficient support. Namely, the supporter hole 205 maybe positioned further inside than the outermost lens hole 235.

The horizontal coupling unit HH and the vertical coupling unit VH may bedisposed along the corner area of the reflecting sheet 126. Thehorizontal coupling unit HH and the vertical coupling unit VH may beinserted into the protrusions of the frame 130 (refer to FIG. 10).

FIG. 19 shows one edge area of the reflecting sheet 126.

Outermost lens holes 235 a to 235 c may mean the lens hole 235positioned on the outermost side. Among the outermost lens holes 235 ato 235 c, the first and second outermost lens holes 235 a and 235 bpositioned on the upper side may be separated from the lower side of thehorizontal dot area HDA by a first distance HDS and may be separatedfrom the upper side of the horizontal dot area HDA by a second distanceHDE. Among the outermost lens holes 235 a to 235 c, the first and thirdlens holes 235 a and 235 c positioned on the side may be separated fromthe lower side of the vertical dot area VDA by a third distance VDS andmay be separated from the upper side of the vertical dot area VDA by afourth distance VDE.

The first distance HDS may be different from the third distance VDS, andthe second distance HDE may be different from the fourth distance VDE.This means that a width, a length, etc., of the horizontal dot area HDAmay be different from a width, a length, etc., of the vertical dot areaVDA.

The first distance HDS may be greater than the third distance VDS.Namely, a distance between the horizontal dot area HDA and the lens hole235 is greater than a distance between the vertical dot area VDA and thelens hole 235.

The second sheet area 126 b (refer to FIG. 11) corresponding to thehorizontal dot area HDA may be shorter than the second sheet area 126 b(refer to FIG. 11) corresponding to the vertical dot area VDA. Becauselengths of the long side and the short side of the second sheet area 126b are different from each other, a slope of the round chamfer of thevertical dot area VDA on the short side may be greater than a slope ofthe round chamfer of the horizontal dot area HDA on the long side. Anincrease in the slope may increase a reflectance. When the reflectanceincreases, a corresponding portion may look brighter. In the reflectingsheet 126 according to the embodiment of the invention, because thevertical dot area VDA is positioned closer to the lens hole 235 than thehorizontal dot area HDA, the reflectance may be controlled in spite ofthe high slope of the vertical dot area VDA on the short side of thereflecting sheet 126.

The non-dot area NDA may be positioned between the horizontal/verticaldot area HDA or VDA and a horizontal/vertical margin area HM or VM.Namely, the non-dot area NDA not including the dot DT may be positionedon the horizontal/vertical dot area HDA or VDA, so that the userwatching the display device 100 cannot recognize the dots DT. Thenon-dot area NDA is formed considering that the dots DT may berecognized from the outside when the dots DT exist in a correspondingarea.

The horizontal and vertical margin areas HM and VM may correspond to thethird sheet area 126 c. Namely, the horizontal and vertical margin areasHM and VM may be an outermost area of the reflecting sheet 126. In otherwords, the horizontal and vertical margin areas HM and VM may be an areaof the reflecting sheet 126 contacting the third frame area 130 c of theframe 130 (refer to FIG. 11). The dots DT may not exist in thehorizontal/vertical margin area HM or VM.

A gap CR may exist between the horizontal margin area HM and thevertical margin area VM. The reflecting sheet 126 may be a plane.Namely, the reflecting sheet 126 may be a two-dimensional plane. Whenthe reflecting sheet 126 of the two-dimensional shape is coupled to thereceiving unit 132 (refer to FIG. 10) of the three-dimensional shape,the reflecting sheet 126 may be changed into the three-dimensionalshape. The shape of the reflecting sheet 126 may be changed byoverlapping at least a portion of the reflecting sheet 126 along thecutting portion S1. A shadow may be generated by the overlap of thereflecting sheet 126. The gap CR may prevent the overlap of thereflecting sheet 126 and thus suppress the generation of the shadow.

A folded portion S2 may extend from an end of the cutting portion S1.The folded portion S2 may not be cut, unlike the cutting portion S1. Thefolded portion S2 may be formed by previously folding a correspondingarea along the cutting portion S1. Thus, when the reflecting sheet 126is changed into the three-dimensional shape in the receiving unit 132(refer to FIG. 10), the reflecting sheet 126 may be guided by the foldedportion S2 and may be changed into a previously designed shape.

FIG. 20 illustrates a dot distribution of a reflecting sheet accordingto an example embodiment of the invention.

As shown in FIG. 20, the dot area DA may exist on the reflecting sheet126. For example, the dots may be distributed along the short sides ofthe display device 100. For example, the dots may be distributed in thesecond area 126 b (refer to FIG. 13) of the reflecting sheet 126. Asdescribed above, the dot area DA may include a horizontal dot area HDAand a vertical dot area VDA. A description of one of the horizontal dotarea HDA and the vertical dot area VDA is equally applied to the other,except in the instance where the horizontal dot area HDA and thevertical dot area VDA are separately described.

The arrangement of the dots DT in the dot area DA may be related to thearrangement of the lens holes 235. As described above, the lens hole 235may correspond to the light source 203 (refer to FIG. 10) and the lens124 b (refer to FIG. 10).

The plurality of lens holes 235 may be disposed on the reflecting sheet126 in accordance with a predetermined rule. Some of the plurality oflens holes 235 may be disposed adjacent to the dot area DA. For example,the lens holes 235 may be separated from the dot area DA by apredetermined distance and may be disposed in parallel with each other.

A first area AR1 and a second area AR2 may be formed based on the lensholes 235. For example, the first area AR1 may correspond to an outmosthole among the lens hole 235, and the second area AR2 may be positionedbetween the first areas AR1. For example, the first area AR1 may be anarea including the lens hole 235, and the second area AR2 may be an areabetween the lens holes 235.

The dots DT disposed in the first area AR1 and the second area AR2 mayhave different attributes. For example, a pattern of the dot included inthe first area AR1 may be different from a pattern of the dot includedin the second area AR2. The pattern of the dot may mean at least onegroup of a size, a density, a color, and an arrangement of the dots DT.For example, at least one of a size, a density, and a color of the dotDT in the first area AR1 may be different from at least one of a size, adensity, and a color of the dot DT in the second area AR2. Thedifference is because intensities of light beams reaching the first areaAR1 and the second area AR2 may be different from each other dependingon a distance between the lens hole 235 and the first area AR1 and thesecond area AR2.

A size of a specific dot included in the first area AR1 may be differentfrom a size of a specific dot included in the second area AR2. The dotsof the first and second areas AR1 and AR2 may be different from eachother in a location. For example, a size of a first dot included in thefirst area AR1 may be different from a size of a second dot which isincluded in the second area AR2 and is closer to the first sheet area126 a than the first dot.

FIGS. 21 and 27 illustrate a dot distribution of a reflecting sheetaccording to an example embodiment of the invention.

As shown in FIG. 21, dots DT may be disposed in a horizontal dot areaHDA and a vertical dot area VDA in various shapes.

The horizontal dot area HDA may be a dot area DA formed on the long sideof the reflecting sheet 126, and a vertical dot area VDA may be a dotarea DA formed on the short side of the reflecting sheet 126. Detailedlocations of the horizontal dot area HDA and the vertical dot area VDAwill be described in corresponding paragraphs.

As shown in (a) of FIG. 21, the horizontal dot area HDA and/or thevertical dot area VDA may be divided into a plurality of areas. Forexample, the horizontal dot area HDA and/or the vertical dot area VDAmay be divided into an uppermost area A, a leftmost area B, a rightmostarea D, a lowermost area E, and/or a an inner area C. The horizontal dotarea HDA and/or the vertical dot area VDA may be divided in differentmanners.

Dots in the plurality of areas of the horizontal dot area HDA and/or thevertical dot area VDA may have different attributes. For example, a sizeand/or a density of a dot DT in the uppermost area A may be greater thana size and/or a density of a dot DT in the lowermost area E. A sizeand/or a density of a dot DT in the inner area C may be greater than asize and/or a density of dots DT in the leftmost area B and therightmost area D.

As shown in (b) of FIG. 21, the horizontal dot area HDA and/or thevertical dot area VDA may not be divided into a plurality of areas.Namely, the dots DT, of which the attributes gradually change, may bedisposed. For example, a size and/or a density of the dot DT mayincrease as the dot DT goes to the upper side of the horizontal dot areaHDA and/or the vertical dot area VDA. The size and/or the density of thedot DT may decrease as the dot DT goes to the inner side of thehorizontal dot area HDA and/or the vertical dot area VDA.

As shown in (c) of FIG. 21, attributes of dots DT in an inner area andan outer area of the horizontal dot area HDA and/or the vertical dotarea VDA may change. For example, a dot DT having a relatively smallsize may be disposed at a boundary between the left and right sidesand/or the lower side of the horizontal dot area HDA and/or the verticaldot area VDA. A dot DT having a relatively large size may be disposed ata boundary between the inner side and/or the upper side of thehorizontal dot area HDA and/or the vertical dot area VDA.

The attribute of the dot DT including the size may change gradually ornon-gradually. For example, in an area ranging from the outer area tothe inner area of the horizontal dot area HDA and/or the vertical dotarea VDA, the size of the dot DT may gradually change or may changedepending on a location. For example, the size of the dot DT in a firstarea including the left and right sides of the horizontal dot area HDAand/or the vertical dot area VDA may be different from the size of thedot DT in a second area including the inner side of the horizontal dotarea HDA and/or the vertical dot area VDA. In other words, there may bea difference in at least one of the size, the color, the interval, andthe density of the dots DT disposed in a horizontal direction and/or avertical direction of the horizontal dot area HDA and/or the verticaldot area VDA. For example, in an instance of the horizontal dot areaHDA, sizes of two dots DT positioned adjacent to each other in thehorizontal direction of the horizontal dot area HDA may be differentfrom each other. The arrangement of the dots DT may be related to thelens hole positioned along the horizontal direction of the horizontaldot area HDA. Namely, a portion, in which the lens hole is positioned,may be brighter, and other areas may be darker. The dots DT havingdifferent attributes may be arranged along the horizontal direction ofthe horizontal dot area HDA, so as to prevent a luminance difference, inwhich a brighter portion and a darker portion are present.

As shown in FIG. 22, dots constituting the horizontal dot area HDA andthe vertical dot area VDA may have different attributes. For example, asize range of the dots constituting the horizontal dot area HDA may begreater than a size range of the dots constituting the vertical dot areaVDA. Namely, the horizontal dot area HDA may include relatively smallerdots and relatively larger dots than the vertical dot area VDA. In otherwords, a diversity of the dots constituting the horizontal dot area HDAmay be more than a diversity of the dots constituting the vertical dotarea VDA. For example, the smallest dot in the horizontal dot area HDAmay be smaller than the smallest dot in the vertical dot area VDA, andthe largest dot in the horizontal dot area HDA may be larger than thelargest dot in the vertical dot area VDA. For example, the smallest dotof the horizontal dot area HDA may have the size equal to or less than0.5 mm, and the largest dot of the horizontal dot area HDA may have thesize equal to or greater than 2 mm. On the other hand, the smallest dotof the vertical dot area VDA may have the size equal to or less than 0.8mm, and the largest dot of the vertical dot area VDA may have the sizeequal to or greater than 1.2 mm. For example, when the sizes of the dotsincluded in the horizontal dot area HDA are divided into “A” groups andthe sizes of the dots included in the vertical dot area VDA are dividedinto “B” groups, A is greater than B. In other words, a size diversityof the dots included in the horizontal dot area HDA may be more than asize diversity of the dots included in the vertical dot area VDA.

An amount range of the dots constituting the horizontal dot area HDA maybe greater than an amount range of the dots constituting the verticaldot area VDA. For example, when the dots having the same size are used,a number of dots included in the horizontal dot area HDA may be more orless than a number of dots included in the vertical dot area VDA.

As shown in FIG. 23, attributes of the dots DT constituting thehorizontal dot area HDA and/or the vertical dot area VDA may changedepending on the area.

The horizontal dot area HDA may include first to third horizontal dotareas HDA1 to HDA3. Namely, the dot area DA may be divided into aplurality of areas. The first horizontal dot area HDA1 may be an areaincluding both sides of the horizontal dot area HDA and may be aboundary area in an inside direction of the reflecting sheet 126. Thesecond horizontal dot area HDA2 may be an area inside the firsthorizontal dot area HDA1, and the third horizontal dot area HDA3 may bean area inside the second horizontal dot area HDA2.

The dots DT in the first to third horizontal dot areas HDA1 to HDA3 mayhave different attributes. Namely, there may be a difference between thedots DT of the first to third horizontal dot areas HDA1 to HDA3 in atleast one of a size, a density, and a color of the dot DT. For example,the dots DT included in the first horizontal dot area HDA1 may be thesame as one another in at least one of the size, the distance, thedensity, and the color. However, the dot DT of the first horizontal dotarea HDA1 may be different from the dot DT of the second horizontal dotarea HDA2 in at least one of the size, the distance, the density, andthe color. Considering the above description, each of the first to thirdhorizontal dot areas HDA1 to HDA3 may be regarded as the gathering ofthe dots DT1 having the same attribute.

The vertical dot area VDA may include first to third vertical dot areasVDA1 to VDA3. The dots DT constituting the first to third vertical dotareas VDA1 to VDA3 may have different attributes. The above descriptionof the first to third horizontal dot areas HDA1 to HDA3 of thehorizontal dot area HDA may be equally applied to the first to thirdvertical dot areas VDA1 to VDA3 of the vertical dot area VDA.

The horizontal dot area HDA and the vertical dot area VDA may beadjacent to four corner areas of the reflecting sheet 126. For example,the horizontal dot area HDA may be disposed on one side of a cuttingportion S1, and the vertical dot area VDA may be disposed on the otherside of the cutting portion S1. The first horizontal dot area HDA1 andthe first vertical dot area VDA1 may be positioned in an area includingthe corner area close to the horizontal dot area HDA and the verticaldot area VDA

Because the corner area is relatively far away from the lens hole 235,the corner area may be relatively dark. Thus, the dot DT may not bedisposed in the middle of the corner area. The dots DT having arelatively high reflectance may be disposed in the first horizontal dotarea HDA1 and the first vertical dot area VDA1 close to the corner area.For example, the relatively small dots DT may be disposed. For example,the dots DT having the relatively low density may be disposed.

As shown in FIG. 24, the plurality of lens holes 235 may be divided intoa first lens hole group 235 a and a second lens hole group 235 bdepending on a distance between the lens holes 235 and the dot area DA.For example, the first lens hole group 235 a may include the lens holes235 adjacent to the dot area DA, and the second lens hole group 235 bmay include the lens holes 235 in the rear of the first lens hole group235 a.

A portion of light emitted from the second lens hole group 235 b may beshielded by the first lens hole group 235 a. For example, a shieldingarea LH may be formed. The brightness of a corresponding area may beless than the brightness of other area because of the shielding area LH.Thus, the dots DT of the shielding area LH and the dots DT of other areamay be differently configured. For example, a size of the dot DTr in atleast a portion of the shielding area LH may be different from that inthe other area.

As shown in FIG. 25, a shape of the dot area DA may be changed dependingon a location of the lens hole 235. For example, the dot area DA mayinclude a first area AR1 including the lens hole 235 and a second areaAR2 except the first area AR1 from the dot area DA. The first area AR1may protrude to the lens hole 235 further than the second area AR2. Forexample, a protrusion area PD may be added to the dot area DA. Aluminance of an area close to the lens hole 235 may be reduced by theprotrusion area PD. The dots DT constituting the protrusion area PD maybe different from the dots DT of other area.

The dots DT of the protrusion area PD may be different from other areasdots. In other words, although the protrusion area PD is included in thefirst area AR1, a size of a dot included in the protrusion area PD maybe different from the size of the dot included in the first area AR1.For example, it is possible that a size and/or a density can be largerin the dots of the protrusion area PD. The reflection can be controlledby changing an attribute of the dot in the protrusion area PD.

As shown in FIG. 26, the shape of the dot area DA may be changeddepending on a relative location between the dot area DA and the lenshole 235. For example, as described above, the first area AR1corresponding to the lens hole 235 may include the protrusion area PDprotruding to the lens hole 235.

A first dot DT1 constituting the protrusion area PD may be differentfrom a second dot DT2 in the rear of the first dot DT1.

A shape of the horizontal dot area HDA may be different from a shape ofthe vertical dot area VDA. For example, the protrusion area PD may beincluded only in one of the horizontal dot area HDA and the vertical dotarea VDA. This may be related to the fact that a number of lens holes235 in the horizontal dot area HDA is more than a number of lens holes235 in the vertical dot area VDA. An attribute of a dot closest to thefirst sheet area 126 a in the first area AR1 may be different from anattribute of a dot closest to the first sheet area 126 a in the secondarea AR2. In other words, the attribute of the dot positioned on theinnermost side in the first area AR1 may be different from the attributeof the dot positioned on the innermost side in the second area AR2. Forexample, a size of a dot positioned on the innermost side in the firstarea AR1 of the vertical dot area VDA may be different from a size of adot positioned on the innermost side in the second area AR2 of thevertical dot area VDA.

As shown in FIG. 27, each of the horizontal dot area HDA and thevertical dot area VDA disposed on the reflecting sheet 126 may have aspecific shape. For example, a height and/or a width of the horizontaldot area HDA and/or the vertical dot area VDA may be differently setdepending on a location.

The horizontal dot area HDA may be divided. For example, the horizontaldot area HDA may be divided into first to third horizontal areas HA1 toHA3. The second horizontal area HA2 may be a center area of thehorizontal dot area HDA. The first and third horizontal areas HA1 andHA3 may correspond to both sides of the second horizontal area HA2.

The first and third horizontal areas HA1 and HA3 may have a shapedifferent from the second horizontal area HA2. For example, the firstand third horizontal areas HA1 and HA3 may have a shape protruding tothe inside of the reflecting sheet 126 further than the secondhorizontal area HA2. For example, the second horizontal area HA2 mayhave a fourth height H4. The fourth height H4 may be less than at leastone of first to third heights H1 to H3. The shape difference may bebecause the first and third horizontal areas HA1 and HA3 are closer tothe corner of the reflecting sheet 126 than the second horizontal areaHA2. Namely, because the reflecting sheet 126 has the rounded shape inthe horizontal and vertical directions at the corner of the reflectingsheet 126, the luminance needs to be more precisely controlled.

In the first and third horizontal areas HA1 and HA3, the horizontal dotarea HDA may have the shape protruding in a predetermined pattern alongthe inside direction of the reflecting sheet 126. For example, thehorizontal dot area HDA may have the shape protruding by the firstheight H1 and the second height H2 and then protruding by the thirdheight H3. The first and third heights H1 and H3 may be greater than thesecond height H2. The first and third heights H1 and H3 may be differentfrom each other. For example, the first heights H1 may be greater thanthe third height H3. The horizontal dot area HDA of the first height H1and the horizontal dot area HDA of the third height H3 may be formedbetween the lens holes 235. For example, the horizontal dot area HDA ofthe first and third heights H1 and H3 may be formed in first and secondareas A1 and A2 between the lens holes 235. Because light beams emittedfrom the plurality of lens holes 235 overlap each other through theabove-described shape of the horizontal dot area HDA, the brightness ofthe first and second areas A1 and A2 may be efficiently controlled.

FIG. 27 shows that the horizontal dot area HDA has the first to fourthheights H1 to H4, as an example. The vertical dot area VDA having theheight/the width different from the horizontal dot area HDA may beconfigured, so as to achieve the same or similar configuration andeffect.

The embodiments and/or the configurations of the invention may becombined with each other. For example, a configuration “A” described inone embodiment of the invention and the drawings and a configuration “B”described in another embodiment of the invention and the drawings may becombined with each other. Namely, although the combination between theconfigurations is not directly described, the combination is possibleexcept in the instance where it is described that the combination isimpossible. This is certain considering that the embodiment of theinvention relates to the display device.

Any reference in this specification to “one embodiment,” “anembodiment,” “exemplary embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the scope of the principles of thisdisclosure. More particularly, various variations and modifications arepossible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A backlight unit comprising: a frame including abottom and a sidewall extending from the bottom; at least one substratelocated on the frame, and a plurality of light sources mounted on the atleast one substrate; and a reflecting sheet located on the at least onesubstrate, wherein the reflecting sheet comprises: a first sheet partlocated on the bottom, the first sheet part including a plurality ofholes corresponding to the plurality of the light sources; a secondsheet part extended from the first sheet part, the second sheet partincluding first areas and second areas; and a third sheet part extendedfrom the second sheet part and located on the sidewall, wherein thefirst areas correspond to outermost holes among the plurality of holes,and the second areas are located between the first areas, wherein a dotpattern in the first areas is different from a dot pattern in the secondareas, wherein the dot pattern in at least one of the first areas andthe second areas comprises a plurality of dot areas positionedsequentially in a direction from the first sheet part to the third sheetpart, the plurality of dot areas including first dot areas and seconddot areas, the first dot areas including a plurality of dots having thesame size and the second dot areas including a plurality of dots havingthe same size, and wherein a size of the plurality of dots in the firstdot areas is different from a size of the plurality of dots in thesecond dot areas.
 2. The backlight unit of claim 1, wherein at least oneof the first dot areas and the second dot areas protrudes toward thefirst sheet part.
 3. The backlight unit of claim 2, wherein the firstdot areas protrudes toward the first sheet part.
 4. The backlight unitof claim 2, wherein the first dot areas protrudes toward the first sheetpart excluding one first dot area adjacent to a corner of the reflectingsheet.
 5. The backlight unit of claim 1, wherein the first dot areashave the same first dot pattern, and the second dot areas have the samesecond dot pattern different from the first dot pattern.
 6. Thebacklight unit of claim 1, wherein the pluralities of dots of the firstdot areas and the second dot areas are positioned on a horizontal dotarea formed along a first side of the reflecting sheet and a verticaldot area formed along a second side of the reflecting sheet, and whereina first distance between a point nearest to the third sheet part in thehorizontal dot area and a hole nearest to the horizontal dot area amongthe plurality of holes is different from a second distance between apoint nearest to the third sheet part in the vertical dot area and ahole nearest to the vertical dot area.
 7. The backlight unit of claim 1,wherein the pluralities of dots of the first dot areas and the seconddot areas are positioned on a horizontal dot area formed along a firstside of the reflecting sheet and a vertical dot area formed along asecond side of the reflecting sheet, and wherein a third distancebetween a point nearest to the first sheet part in the horizontal dotarea and a hole nearest to the horizontal dot area among the pluralityof holes is different from a fourth distance between a point nearest tothe first sheet part in the vertical dot area and a hole nearest to thevertical dot area.
 8. The backlight unit of claim 1, wherein thepluralities of dots of the first dot areas and the second dot areas arepositioned on a horizontal dot area formed along a first side of thereflecting sheet and a vertical dot area formed along a second side ofthe reflecting sheet, and wherein a fifth distance between a pointnearest to the first sheet part and a point nearest to the third sheetpart in the horizontal dot area is different from a sixth distancebetween a point nearest to the first sheet part and a point nearest tothe third sheet part in the vertical dot area.
 9. The backlight unit ofclaim 1, wherein a size of a dot of the first dot areas nearest to thefirst sheet part is different from a size of a dot of the second dotareas nearest to the first sheet part.
 10. The backlight unit of claim1, wherein, in the second sheet part, at least one of a size and adensity of the pluralities of dots of the first dot areas and the seconddot areas increases as the pluralities of dots approach the third sheetpart.
 11. The backlight unit of claim 1, wherein, in the second sheetpart, at least one of a size and a density of the pluralities of dots ofthe first dot areas and the second dot areas increases as thepluralities dots approach the third sheet part along an imaginary lineconnecting a first point of a corner area of the reflecting sheet and asecond point closest to the third sheet part in the middle of the secondsheet part.
 12. The backlight unit of claim 1, wherein, in the secondsheet part, at least one of a size and a density of dots of a first areaadjacent to the third sheet part is different from at least one of asize and a density of dots of a second area except the first area. 13.The backlight unit of claim 12, wherein the first area is one of thefirst dot areas, and at least one of a size and a density of at leastone dot of the first area is smaller than at least one of a size and adensity of at least one dot of the second dot areas.
 14. The backlightunit of claim 1, wherein the pluralities of dots of the first dot areasand the second dot areas are positioned on a horizontal dot area formedalong a first side of the reflecting sheet and a vertical dot areaformed along a second side of the reflecting sheet, and wherein at leastone of the horizontal and vertical dot areas has different widths, thewidths being in a direction from the first sheet part to the third sheetpart.
 15. The backlight unit of claim 14, wherein at least one of thehorizontal and vertical dot areas comprises a center area and side areaspositioned on the sides of the center area, and a width of the centerarea is smaller than widths of the side areas.
 16. The backlight unit ofclaim 15, wherein a dot pattern of the center area is different from adot pattern of the side areas.
 17. The backlight unit of claim 15,further comprising at least one protrusion area protruding from the sideareas to the first sheet part.
 18. The backlight unit of claim 17,wherein at least one of a size and a density of at least one dot of theat least one protrusion area is different from at least one of a sizeand a density of at least one dot adjacent to the at least oneprotrusion area.
 19. The backlight unit of claim 15, wherein a width ofat least a portion of the at least one horizontal dot area is differentfrom a width of at least another portion of the at least one horizontaldot area.
 20. The backlight unit of claim 1, wherein each of the firstareas corresponds to each of the outermost holes among the plurality ofholes.